In late 1944, the Heinkel firm designed this project to meet a RLM specification for a fast piston-engined fighter with an good high altitude performance. Designer Siegfried Günter used the He 100 design (which briefly held the world speed record at 746.606 km/h (463 mph) on March 30, 1939) as his inspiration.
Source : http://www.luft46.com/heinkel/hep1076.html